Who laps scope rings?

[Ledd Slinger]

None taken. My example was a rifle shot on a weighted down sled. It stops the rearward movement so basically the rifle is pounding the sled. This is with the sled weighted down with 50lbs plus of lead. I've seen two scopes fall apart on muzzleloaders when they were shot in a sled. The mounts held up though.

I see. Interesting. I always thought a rifle butt was rested against the rear of the Lead Sled when firing so that it did not slide and slam the rest. I don't use that rest so I don't claim to be an expert on it, but I have seen it used by others a few times and the rifles did not slide in the rest when fired. Only the muzzle jumped when they didn't have it strapped down.

 

[Alex Wheeler]

My opinion on lapping. If this is a recoiling rifle like a 300 win or 7mm mag, you want to lap the rings to remove the anodizing or the scope will slip in the rings. I have had this happen a lot. I only lap the bottoms of the rings. If this is an all out build, I lap the rings then bed them. I have seen quite a few slipped scopes and bases lately. Enough that pinned bases and lapped or bedded rings should be standard on anything with a decent amount of recoil.

 

[Ledd Slinger]

Just a few pics for the OP on the scope I just set the other day.

Lapped rings with a .024" thick shim which was calculated off of ring spacing to allow for 20 MOA extra elevation. I actually apply the bedding then press the shim into the bedding dead center of the rear ring. I lapped these rings liberally 3 times with 220 grit compound and you can see it still did not remove all of the anodizing. They are cheaper rings and bases, but the lapping and bedding make up for all the misalignment. I've had very expensive rings and bases give me similar results many times in the past so I no longer see the need to spend extra money on 'quality' rings and bases. I take decent rings and MAKE them into quality rings with my method. I use Kiwi neutral shoe polish as a release agent on the scope body. Set scope, level it, hand tighten rings and ensure they have even gaps, let it cure for 3 hours, remove excess bedding while it's still gummy, finish curing for 24 hrs, pop out scope, remove all residue with automotive air intake cleaner, trim and sand edges of bedding, reset scope with leveling system, torque ring screws to 20 inch lbs, bore sight at 50 yards and I'm off to the range. Nothing to it...ok it's a pain, but well worth it in my opinion




PS: don't mind my bare bolt knob that looks out of place. Just put that on and need to finish it with black accents.

 

[BoydAllen]

Bravo....Well done.

 

[savagedasher]

The reason I see for lapping is so the. Scope Movement wouldn't be in a bind .
Kind of like line boring a block .
I don't understand why just the bottom but if you skim Bed the tops it would work . Larry

 

[Ledd Slinger]

Funny you say that Larry. A bound up scope that wouldn't adjust properly is EXACTLY what pushed me into doing my rings this way. I lap top and bottom parts of the rings and bed both as well. Was actually caused by a Savage rifle having a warped receiver. No offense to anyone who likes Savage, but I haven't owned any savage rifles after that incident because it made me so mad. That case was actually so bad I had to shim and bed under right hand side of the rear portion of the base as well.

Mr. Alex Wheeler, who is in on this thread now, was the one who taught me this entire bedding and shimming method with advice through a string of PM's a while back. I consider it one of the best things anyone has ever taught me for tinkering with rifles. Really changed the whole game for me on scope reliability. Thanks for that Alex

When I bore sighted the above pictured scope at 50 yards, it was dead nuts on for windage while at optical center (of course that may change slightly when i actually shoot it). All I had to do was compensate the elevation for the shim. So it's about as perfect as can be so far.

I also check that every single turret click from the first to the last on elevation and windage is actually moving the reticle. This step is extremely important in verifying the job has been done properly. And not only moving, but not getting harder to adjust when reaching the end limits. A good scope turret should just stop when it reaches the end. Not get really hard for the last handful clicks. Of course this can't always be expected with cheap scopes. But for mid priced on up, the turrets are usually built pretty well and will function very reliably when the scope body is perfectly aligned. Ive never been able to consistently align windage so closely to optical center by lapping alone so I always bed them. With bedding I've never been more than a few clicks off of optical center for windage when boresighting.

 

[savagedasher]

Funny you say that Larry. A bound up scope that wouldn't adjust properly is EXACTLY what pushed me into doing my rings this way. I lap top and bottom parts of the rings and bed both as well. Was actually caused by a Savage rifle having a warped receiver. No offense to anyone who likes Savage, but I haven't owned any savage rifles after that incident because it made me so mad. That's case was actually so bad I had to shim and bed under right hand side of the rear portion of the base as well.

Mr. Alex Wheeler, who is in on this thread now, was the one who taught me all this with advice through a string of PM's a while back. I consider it one of the best things anyone has ever taught me for tinkering with rifles. Really changed the whole game for me on scope reliability. Thanks for that Alex

When I bore sighted the above pictured scope at 50 yards, it was dead nuts on for windage while at optical center (of course that may change slightly when i actually shoot it). All I had to do was compensate the elevation for the shim. So it's about as perfect as can be so far.

I also check that every single turret click from the first to the last on elevation and windage is actually moving the reticle. This step is extremely important in verifying the job has been done properly. And not only moving, but not getting harder to adjust when reaching the end limits. A good scope turret should just stop when it reaches the end. Not get really hard for the last handful clicks. Of course this can't always be expected with cheap scopes. But for mid priced on up, the turrets are usually built pretty well and will function very reliably when the scope body is perfectly aligned. Ive never been able to consistently align windage so closely to optical center by lapping alone so I always bed them. With bedding I've never been more than a few clicks off of optical center for windage when boresighting.

I think scope ring missed alignment and location is the problem of many scopes especially with the light weight . Larry

 

[BoydAllen]

Having lapped many sets of rings over the years, both expensive and cheap, I can tell you that one never knows exactly what he has until a little lapping has been done.

On the alignment thing. I have a Savage 110 action that is now part of a parts varmint rifle that shoots very well for the barrel that it has on it. The scope base holes are so far off that in order to correct the problem I used 1" Signature Zee rings with +- .020 inserts in both rings, with their parting lines vertical, and their offsets in opposite directions, the equivalent of a single ring offset of .040. With this setup I ended up very close to center of target with the scope's reticle centered... within an inch.

Back in the day, I attended a presentation that Burris made at a Shot Show, across a table from Jim Carmichael. The whole thing was put on to introduce their new Posalign (now signature) line of rings. The fellow who was presenting told us that he had gotten the idea while changing the center bearing in the two piece driveshaft of an old Ford pickup. I smiled because at the time Jewel was offering rings with spherical aluminum self aligning inserts, not with offsets but still very similar. When I got back from the show, I called Arnold to see if Burris was stepping on any patents. He laughed and told me that no one can patent the idea because it had been patented years before and the patent had run out. So for all of you small production shops....

I have bedded exactly one set of rings, after I had grown weary lapping a set of Ruger steel rings on a model 77 varmint rifle. They were very far off and I had only gotten about half way there. Too timid to use the scope, I measured the lapping bar, and it was very close to the diameter of my scope, so I cleaned off the grit and grease from both the rings and the bar, waxed the bar twice with Kiwi neutral, and used the bar to bed the rings. It worked very well. The scope seemed to form a suction fit with the rings. I used a small hardware store Devcon Plastic Steel kit. This was probably more than 30 years ago.

 

[JRS]

The best rings in the world can't fix a reciever that's not true or a base/rail that doesn't fit properly!

If the bases are properly installed, you won't need to lap quality rings. Lapping quality rings is a fix for a different problem.

 

[Gary in MD]

I never had any of these issues 45 years ago.....
Walking around with my open sighted pellet rifle as a kid- everything I pointed it at died!

 

[msinc]

.......Burris Zee rings work well for straightening a scope on the rifle, but not to be trusted on high recoil hunting rifles or packing in the mountains where you could take a fall. They will not hold up on hard impact........

You got me curious now Ledd Slinger....I have used these rings several times and I thought they worked pretty good...what sort of problems have you had with them??? I haven't thrown a rifle off the mountain lately either {I am about due though!!!}, what breaks or doesn't hold up??? I always slide them forward in the slot before tightening and I did have a guy bring me a rifle that he wrung one of the bolts off in from over tightening, but other than that I have had pretty good performance with them.
I have been using Leupold dual dovetail rings a lot lately on hunting rifles and I find that as long as I use points to align them carefully they very rarely need any lapping and if so it is usually not much at all.
I have been very lucky when it comes to bad receivers and poor bases...I have had one of each and that was a while ago...but I have seen it plenty of times. Both of mine were too bad for lapping to cure.

EDit: I have great respect for Mr. Boyer. Anyone that unselfishly shares with others his lifetime of knowledge in a field where he has excelled while most others choose to "keep it to themselves" has got my vote. That said, there is one thing in his book that I find "interesting".....given all the nit pickety a$$ little things he does to get a rifle to shoot, there's a page where he talks a little about bullet concentricity. He describes being at a match and a guy has concentricity gauges for sale, so he checks some of his ammo. They test like .005" to .008" IIRC and decides that he "doesn't need that tool"......I guess you cant argue with results!!! I mean, he's worried about polishing the action spring with 600 grit sand paper and totally dismisses a bullet being seated straight in the case.........hands to the sky and bow repeatedly...we are not worthy great master...we are not worthy.....

 

[Ledd Slinger]

Burris Zee rings are fine for varmint rifles and competition shooting. Will even handle a good bit of recoil I'm sure. But when it comes to rifles that will be packed into the mountains, the rings you see in the picture are as light as I'm willing to go. Some rifles I use 6 screw rings. I've taken some hard falls on snowy mountainsides and although I always try to protect my scope like it was an open can of beer, Im not always successful. 6 screw rings have never lost zero for me. Leupold and Burris Zee have. It's always the point of the ring where it attaches to the base that I've seen fail. Only happened to me personally one time, but thats all i need to learn my lesson. Seen it a few times on other folks rifles. They have their place, theyre just not for me on my big game hunting rifles.

 

[BoydAllen]

You got me curious now Ledd Slinger....I have used these rings several times and I thought they worked pretty good...what sort of problems have you had with them??? I haven't thrown a rifle off the mountain lately either {I am about due though!!!}, what breaks or doesn't hold up??? I always slide them forward in the slot before tightening and I did have a guy bring me a rifle that he wrung one of the bolts off in from over tightening, but other than that I have had pretty good performance with them.
I have been using Leupold dual dovetail rings a lot lately on hunting rifles and I find that as long as I use points to align them carefully they very rarely need any lapping and if so it is usually not much at all.
I have been very lucky when it comes to bad receivers and poor bases...I have had one of each and that was a while ago...but I have seen it plenty of times. Both of mine were too bad for lapping to cure.

EDit: I have great respect for Mr. Boyer. Anyone that unselfishly shares with others his lifetime of knowledge in a field where he has excelled while most others choose to "keep it to themselves" has got my vote. That said, there is one thing in his book that I find "interesting".....given all the nit pickety a$$ little things he does to get a rifle to shoot, there's a page where he talks a little about bullet concentricity. He describes being at a match and a guy has concentricity gauges for sale, so he checks some of his ammo. They test like .005" to .008" IIRC and decides that he "doesn't need that tool"......I guess you cant argue with results!!! I mean, he's worried about polishing the action spring with 600 grit sand paper and totally dismisses a bullet being seated straight in the case.........hands to the sky and bow repeatedly...we are not worthy great master...we are not worthy.....

One thing that you should be aware of about 6PPC rounds. Necks are typically thin and bullets have pressure rings. Some powders do not require much neck tension, others do. The pressure ring, combined with minimal bullet in neck and thin necks acts like a ball joint, allowing the bullet to be straightened to the chamber as it is loaded. Once I did a similar test using a H&H gauge that is designed to straighten rounds to push one to a runout of .0035 well beyond what my sizer and seaters produce, chambered the round, and remeasured it. It was .0015. In the past I have been told that measurements of .002 and better are sufficiently good, that no further improvement will be seen beyond that point. That is measured on the bullet at or near the point where the rifling will make contact. If Tony had rounds that were as crooked as you mentioned he would have had to take them in his hands and move the bullet in the case neck to produce that level of runout. I am sure that my sizer and seater are no better than his and they typically produce runout around .0015. What probably happened is that he shot groups, they were good, and he went no farther with his inquiry. Back when he did that, he was probably shooting T powder, which does not require neck tension like 133. One thing that concentricity gauges are good for at a match is messing with the other guys minds. One time years ago, I was using the H&H to measure and straighten as I went, loading between individual matches. Soon there was a line of shooters wanting their rounds to be checked. Creating doubt in the minds of the competition can be an advantage, but being able to tune and read flags is a lot more important. For necks that are a lot thicker, sized to more substantial neck tension, using seating depths that have a lot of bullet shank in the neck, it is a whole different situation. I have tried to straighten factory rounds and to do that involves bending case necks of loaded rounds. When I tested the results, there was no improvement that I could see on the target over unsorted, unstraightened rounds.

 

[BoydAllen]

If the bases are properly installed, you won't need to lap quality rings. Lapping quality rings is a fix for a different problem.

Tell me, how do you properly install two piece bases on a crooked misdrilled factory reciever? I would like to learn that trick. Also I have lapped Kelbly rings on a Panda and seen the pattern of contact improve. It was not bad in the first place, but it improved. Tightening rings on a base can distort them. Of course if you make assumptions you will never see this.

 

[JRS]

Tell me, how do you properly install two piece bases on a crooked misdrilled factory reciever? I would like to learn that trick. Also I have lapped Kelbly rings on a Panda and seen the pattern of contact improve. It was not bad in the first place, but it improved. Tightening rings on a base can distort them. Of course if you make assumptions you will never see this.

By fixing the faulty part. That isn't an assumption, it's a fact! Why lap the rings? If you want 100% surface contact, bed the rings. By removing the anodized finish on the rings via lapping, you expose the smooth raw aluminum.

Edit: You can also use the method Bausch & Lomb advocated decades ago…. wipe on a thin layer of rubber cement For base alignment, use a base-bed alignment bar.

 

[savagedasher]

Tell me, how do you properly install two piece bases on a crooked misdrilled factory reciever? I would like to learn that trick. Also I have lapped Kelbly rings on a Panda and seen the pattern of contact improve. It was not bad in the first place, but it improved. Tightening rings on a base can distort them. Of course if you make assumptions you will never see this.

Very simple you don't . Most good rings have witness marks. But they are only as good as what they are fasten to . If the action isn't right you have another problem .
Many of times the rings are positioned in the wrong area on the scope . That impeads the movement inside . Wrong alignment or over tighten pressure in the wrong area you scope turns to junk . Not saying names ! I know of two of the best scopes used that that has been a problem . Larry

 

[Prose]

A few years ago I was putting a very cheap scope on a very cheap rifle, and used a 1" pin from a tracker supply store to lap the rings. It worked quite well and I've continued to do it on other set-ups. I think the steel pin and valve grinding compound cost me $8 bucks. Someone earlier mentioned that when you start lapping you generally know what you've got pretty quickly. Four or five passes generally will let a person know if there is a problem or if it's not needed.

 

[USPR]

I do lotsa scope mounting on custom and factory rifles. Misaligned rings can and will bend a scope tube to conform to the misalignment. Mounting a scope inside misaligned rings can never improve a rifle's performance and can only hurt it. I always check the contact surface by using a nice straight SS lapping bar and some 240 grit valve lapping compound. This will tell you right away where are your high spots are. I gotta say, even high quality rings and bases that were built with super accurate CNC machines very seldom provide more than 25% contact surface for a scope to rest on. I typically wind up lapping every set of rings that go through my shop.

 

[Prose]

Very simple you don't . Most good rings have witness marks. But they are only as good as what they are fasten to . If the action isn't right you have another problem .
Many of times the rings are positioned in the wrong area on the scope . That impeads the movement inside . Wrong alignment or over tighten pressure in the wrong area you scope turns to junk . Not saying names ! I know of two of the best scopes used that that has been a problem . Larry

I have seen a proven scope put into unlapped rings and no longer track correctly. Once the rings were lapped it tracked correctly, but had lost some accuracy. An inspection showed that the erector was damaged due to torque on the tube.

 

[Alex Wheeler]

Scopes are delicate instruments. Lapping ensures your not binding a tube. Bedding is even better and will hold a scope much better with less torque. Anodizing on the rings against an anodized tube is asking for a slipped scope. I have done it and could not believe it. You would not think a scope would slip in the rings with medium recoil and properly torqued rings but they do. I use a lot of Talley rings on hunting rifles and I wont let them go without lapping and removing the anodizing on the bottom ring. Most of my work is custom actions, and I dont remember ever lapping a ring in and it not showing some misalignment.